Brake mechanism.



E. FRIEDLAENDEH. BRAKE MEGHANISM.

APPLICATION FILED OCT.. 11, l9l2- 'Patented July 3, 41917.

a I 'myemfon wi'msssss- UNITED STATES PATENTl orifice..

EUGENE FRIEDAENDER, OF BRADDOCK. PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OIF 'PENNSYL- VANIA.

Specification of Letters Patent.

To all whom t may concern Be it knovvn that I, EUGENE Firmanaam nini, a citizen of the United States,'residing at Braddock, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Brake Mechanism, of which thefollowing is a specification.

' My invention has relation to the class of brakes employed `in connection with electric motors in stopping and` controlling the operation of such motors and1 while 4not restricted to suoli use, more particularly relates to theconstruction and arrangement of electrically operated brakes employed in stopping and controlling the operation of the armature shaft of electric motors and of similar devices ordinarily rotated when in luse at a high rate of speed.

One object of my invention is to provide a brake mechanism of strong and durable construction, which is simple in design and adapted to withstand severe usage, having novel means whereby the retarding or brain ing power of the brake is applied and .by which the brake is maintained .in `operative .or holding position.

aiforded, with the lbrake Wheel rotating ineither of opposite directions and by. which the braking and brake holding power is made substantially constant .during the life of the brake slices forming part of the braking mechanism.

Still further objects of this invention will appear hereinafter as the apparatus is' more fully described andclaimed.

Referring to the accompanying drawings :forming part of thisspecification Figure 1 is an elevation showings brake mechanism constructed and arranged and applied for 'use in accordance with my invention.- Fig.

2 is a plan df the apparatus shown in 1 i`ig. 1.

Fig. 3 is a sectional elevation on a slightly smaller scale showing a portion of a modified form of brake mechanismas constructed and arranged and applied for use in accordance withV this invention.

In the drawings, in which. myimprovedl brake mechanism. is shown applied for use with an electric motor, the numeralQ designates the armature shaft of a motor Which may form part of an electric crane, an elevator or hoist operating mechanism or may comprise part of the driving mechanism-of a roller feed table or similar apparatus, wherein it is necessary or desirable to bring the motor to a stop quickly ,after shutting oft' the current, or in which the armature of the motor is to be held against rotation as in cases of sustained loads on such cranes, elevators, hoists and like devices.

Patented July 3, 1917.

Keyed' or otherivie secured on the shaft 70 i 2 so as to rotate therewith is a brake wheel 4l having a flat periphery7 5 which is arranged to be engaged by the opposed brake shoes (i, (S and, preferably, the shoes 6 are removably secured on the curved or bent arms 7, 7 which are pivotally secured at one end b v the pin 8 to lugs 9 on the support or base 10, for the solenoid .by which the y brake mechanism (as will hereinafter be described) is moved and held in inoperative position.

ally connected by pins 11 to one end of the 80 The upper ends of the arms 7 are pivottoggle links 12, 12 and the adjacent overlapping ends of these links 12 are connected by a pin 13n to one end of the links 13,13 which are pivotally connected to one end of the lever 14 by the pin 15.

Provision is made for considerable Wear upon the brake shoes 6 before necessitating the pivoted arms 7 are recesses 18 in which.

the helical springs 19 are mounted and a rod 20 having a screw-threaded end extends throughv the recesses 1S and the followers 21,- and the screw-threaded end of the rod has an adjusting nut 22 and jam nut 23 by which compression of the springs 18 isregulated and the gripping force of the brake shoes 6 on the brake Wheel l is regulated When the brake is setor in operative or holding position.

` The lever lll which is on a pin 24 in the bracket earin 25 formed integrally on thecover 26 fort e solenoid pivotally mounted los casing 27 is connected to the forked' end of.

the plunger frod 27a which is screwed into `the internallywthreaded `upper end of the' S0- 110 lenoid core 28 by which the braking mech anism is actuated. A flange 28a on the upper end of the core 28 is provided by which downward movement of the corel li vnited and a lock or jam nut Q9 serves lo ho d the rod-27EL in adjusted position in the core 28. The solenoid core 28 projects downwardly into the axial opening 30 in the spool 31 ot' the solenoid which as shown is constructed with. a coil 32 on the spool 3l, the coil 3Q being entirely sm'rounded by the metal shell or casing 27, the bottomlof whiclris provided with lugs or flanges by which the solenoid is secured in positionon'the upper fianges on the base 10.

The brake shoes 6 as illustrated are shown unlineihalthough the shoes may be lined with asbestos` which gives a considerably higher eoeflicient of friction with a relatively long life it' an extra strong braking effect is desireil, 'or in cases where oil or grease, which would greatly reduce the friction between the contacting metal faces of the shoes and brake wheel, is liable to get on the wheel. Such v'asbestos lining being affected little if any by oil or water, is particularly well adapted for such uses.'

Suitable provision is made, ordinarily, on the motor base plate for mounting thereb1) on thebase 10` on which the solenoid and brake mechanism are secured. l

The brake operating mechanism as shown in Figs. 1 and 2 is located to .one side of the armature shaft while in Fig. 3 the solenoid positioned directly in front of orin line with the axis of the armature shaft 2.

ln the construction shown in Fig. .3 the link connecting the lever 14 with the toggle links 12, 12 is modified in lconstruction owing 4J to the change in position of the solenoid and base therefor' ou the motor base plate.

relative to the axis of the motor armature shaft.

In the operation of my improved brake mechanism the apparatus is assembled as shownI and the vnuts 22, 23 on the bolt 20 are adjusted so as to compress the springs 19 -to the extent lnecessary to `clamp theshoes (i on the brake wheelt and hold. the arma- I tureshalt 2 and wheel 4 stationary When the current .is shut off from the motor 3 and the crane,v hoist or elevator mechanism of whirl-1 the 'motor forins'partis carrying a load of maximum capacity.

. \Vlien the motor 3 is set in operation, current is caused to `pass through the coil 32 ol the solenoid and when energized, the i-oil 2&2 will cause the solenoid core 28 to move downwardly Within the opening 30 of the spool 31 into which it projects. -The downward movement of the core 28 through the medium o-E the lever 14 will actuate the i'toggle links 12, 12 in such manner as to move l the pivoted arms 'i' away from each other .in the pivot pin 9 by which they are connected to the base 10. This movement of the toggle links will further compress the springs lf) and the movement of the arms 7 will. retract the brake shoes 6 and release the brake wheel. -1 so that the armature shaft 70 2 will rotate freely with the brake shoes 6 out of engagen'ient with thel brake wheel 4: on the shaft Q. v

lhen the current is shut oli" from the motor the solenoid coil 32 is denergized l5 simultaneously therewith. `Then this oc. curs the '-ompressed springs 19 act through the connecting lever mechanism to lift the solenoid core 28 and again throw the toggle links 1.2 into the position sho'wn in Fig. 1 80 of the drawings, in which position the comi pressive torce of the springs 19, 19 is again exerted to move the bra'kc shoesfG tightly into engagement with the periphery' 5 of the brake wheel 'so as to rstirretard and `35 then hold the brake wheel l and armature" shaft 2 connected therewith against rotation. y

As the solenoid core 2S is of considerable weight; the force of thevs )rings 19 iscounter- 90` balanced by the inertia of the core at the time the retarding power is first applied by the shoes G to the brake wheel 4 so that the retarding action ot' the brake shoes is cushioned and made togradually increase which.' 95 tends to lessen the liability of breakage or other aceiiflent to the apparatus.

rl`he above described operations are then repeated asollen as is necessary in the operation of the brake and when the motor is rotated in either of opposite directions.

The advantagespf my invention will be 'apparent to those skilled in the art.

rl`he action of the brake is entirely automatic as it is set by the springs and is released whenever' the solenoid or electro-magnet is energized. The brake is amply strong v to give sufficient braking power with a maximum air gap. The solenoid core' can be easily raised or lowered by means of the adjustable eye bolt 27L whenever it is desired to slacken or loosen the. brake shoes.

'Ihe compressive movement of the springs is very short so that the stresses ari kept low and liability ofbreakagc of the springs is I n'iaterially lessened. The weight of the solenoid eore eounteracts thespring pressure when the setting action of the brake shoesoccurs so that the braking o'r retarding forceiv is gradually applied to the brake wheel. The 126 removable brake shoes are rigidly mounted on the pivoted brake shoe armsand are readily removed and replaced when required.

Modifications in the construction and arrangement of the parts may be made without departing from my invention.

I claim 1.' A brake mechanism comprising a brake wheel, brake shoes operatively engaging with the Wheel, arms on which said brake 'shoes' are removably secured, means on said arms including a rod and coil spring whereby the arms are actuated to move and'hold the brake shoes in engagement with said Wheel, a toggle whereby said arms are actu- .ated to .move the brake shoes, alever operinto inoperative positioni; a pivoted lever connected to said toggle, a solenoid and having a core member adjustably connected to said lever to actuate the toggle and retract the brake shoes out of operative engagement with said brake Wheel, and means integral with said stationary part for supporting said lever.

3. A. brake mechanism comprising a brake wheel, a pivoted arm having a shoe operatively engaging with the Wheel, yielding means whereby said arm is moved to bring and hold the shoe in braking engagement with the Wheel, a toggle connected to said arm to release and hold the brake shoe in disengaged position,` a solenoid, and a lever supported 'b ,said solenoid for operatively and adjusta ly connecting the solenoid to said toggle.

va spring whereby said arms are actuated to move and hold the shoes in braking engagement with the Wheel and a solenoid opera- 4 tively and adjustably connected to sa-id arms to release and hold the shoes in disengaged position.

5. A brake mechanism comprising a brake Wheel, pivoted arms having opposed brake shoes operatively engaging with thebrake Wheel', means Wherebyvsaid arms are actuated to move and hold the shoes in braking engagement with the Wheel, a solenoid co1nprising a casing, and a lever supported by said casing and adjustably operatively connected to said solenoid and said arms.

6. A brake mechanism comprising a brake Wheel, a pivoted arm'` having a brake-Shoe operatively engaging with the brake wheel', means whereby said arm is actuated to move and hold the shoe in braking engagement With the wheel, and a solenoid operatively connected to said arm to release and hold the shoe in disengaged position, said solenoid comprising a relatively heavy core member :for opposing the initial action of said actuating means.

In testimony whereof, I have hereunto set my hand.

`:soenna FRIEDLAENDER.

Witnesses DAVID BLYTH, Ro'r. DRYLm.

Correction in Letters Patent No. 1,231,590.

t is hereby certified that in Letters Patent. No. 1,23l,590, granted July 1917, upon the application of Eugene Fricdlaondser, of Brmldock, Pennsylvania,

for an improvement in "Brake Mechanism, an error appears in the printed Page 3,1im` 19, claim 2, after the specification requiring correction as follows:

word u solenoid insert, he words comprising; a stationary part; und that. the said should-be read with this correction therein that the some muy Letters Patent. conform to the record oi the oase n the Patent Oce.

Signed and sealed this 14r.h day of August, A. D., 1917.

R. v. WHITEHEAD,

[sun] Acting Commissioner of Patents. 

